Semiconductor device having gate dielectric and inhibitor film over gate dielectric

ABSTRACT

One or more semiconductor devices are provided. The semiconductor device comprises a gate body, a conductive prelayer over the gate body, at least one inhibitor film over the conductive prelayer and a conductive layer over the at least one inhibitor film, where the conductive layer is tapered so as to have a top portion width that is greater than the bottom portion width. One or more methods of forming a semiconductor device are also provided, where an etching process is performed to form a tapered opening such that the tapered conductive layer is formed in the tapered opening.

RELATED APPLICATION

This application is a continuation of and claims priority to U.S. patentapplication Ser. No. 16/023,513, presently titled “SEMICONDUCTOR DEVICEHAVING GATE BODY AND INHIBITOR FILM BETWEEN CONDUCTIVE PRELAYER OVERGATE BODY AND CONDUCTIVE LAYER OVER INHIBITOR FILM” and filed on Jun.29, 2018, which is a divisional of and claims priority to U.S. patentapplication Ser. No. 14/208,211, titled “SEMICONDUCTOR DEVICE WITHSIDEWALL PASSIVATION AND METHOD OF MAKING” and filed on Mar. 13, 2014.U.S. patent applications Ser. Nos. 16/023,513 and 14/208,211 areincorporated herein by reference.

BACKGROUND

Complementary metal-oxide-semiconductor (CMOS) technology is asemiconductor technology used for the manufacture of integrated circuits(ICs). CMOS transistors typically utilize a polysilicon or a metal asthe gate electrode for both NMOS and PMOS transistors, wherein the gateelectrode is doped with an N-type dopant to form NMOS transistors and isdoped with a P-type dopant to form PMOS transistors.

BRIEF DESCRIPTION OF THE DRAWINGS

Aspects of the present disclosure are best understood from the followingdetailed description when read with the accompanying figures. It isnoted that, in accordance with the standard practice in the industry,various features are not drawn to scale. In fact, the dimensions of thevarious features may be arbitrarily increased or reduced for clarity ofdiscussion.

FIG. 1 is a flow diagram illustrating a method for fabricating asemiconductor device, according to some embodiments;

FIG. 2 is a cross-sectional view of a semiconductor device duringfabrication, according to some embodiments.

FIG. 3 is a cross-sectional view of a semiconductor device duringfabrication, according to some embodiments.

FIG. 4 is a cross-sectional view of a semiconductor device duringfabrication, according to some embodiments.

FIG. 5a is a cross-sectional view of a semiconductor device duringfabrication, according to some embodiments.

FIG. 5b is a cross-sectional view of a semiconductor device duringfabrication, according to some embodiments.

FIG. 6 is a cross-sectional view of a semiconductor device duringfabrication, according to some embodiments.

FIG. 7 is a cross-sectional view of a semiconductor device duringfabrication, according to some embodiments.

DETAILED DESCRIPTION

The following disclosure provides many different embodiments, orexamples, for implementing different features of the provided subjectmatter. Specific examples of components and arrangements are describedbelow to simplify the present disclosure. These are, of course, merelyexamples and are not intended to be limiting. For example, the formationof a first feature over or on a second feature in the description thatfollows may include embodiments in which the first and second featuresare formed in direct contact, and may also include embodiments in whichadditional features may be formed between the first and second features,such that the first and second features may not be in direct contact. Inaddition, the present disclosure may repeat reference numerals and/orletters in the various examples. This repetition is for the purpose ofsimplicity and clarity and does not in itself dictate a relationshipbetween the various embodiments and/or configurations discussed.

Further, spatially relative terms, such as “beneath,” “below,” “lower,”“above,” “upper” and the like, may be used herein for ease ofdescription to describe one element or feature's relationship to anotherelement(s) or feature(s) as illustrated in the figures. The spatiallyrelative terms are intended to encompass different orientations of thedevice in use or operation in addition to the orientation depicted inthe figures. The apparatus may be otherwise oriented (rotated 90 degreesor at other orientations) and the spatially relative descriptors usedherein may likewise be interpreted accordingly.

One or more semiconductor devices and one or more methods for formingsuch semiconductor devices are provided herein. In some embodiments, asemiconductor device includes at least one of a multi-gate transistor,fin-type multi-gate transistor, a gate-all-around (GAA)metal-oxide-semiconductor field-effect transistor (MOSFET) or a planarmetal gate CMOS. In some embodiments, the semiconductor devices includeat least one of a gate body, a conductive prelayer, an inhibitor film ora conductive layer. In some embodiments, a method including adirectional etching process and a sidewall passivation process areprovided. In some embodiments, the method inhibits the formation ofvoids or seams in at least one of the conductive prelayer or theconductive layer.

Referring to FIG. 1, illustrated is a flow diagram of a method 100 forfabricating a semiconductor device 200 according to some embodiments.Referring also to FIGS. 2 to 8, illustrated are cross-sectional views ofthe semiconductor device 200 at various stages of fabrication accordingto some embodiments, such as according to the method 100 of FIG. 1. Insome embodiments, part of the semiconductor device 200 is fabricatedwith a CMOS process flow. In some embodiments, additional processes areprovided before, during, and after the method 100 of FIG. 1.

At 102, a semiconductor substrate 202 is formed, as illustrated in FIG.2. In some embodiments, the substrate 202 is merely provided or receivedand is not formed as part of method 100. In some embodiments, thesubstrate 202 includes at least one of an epitaxial layer, asilicon-on-insulator (SOI) structure, a wafer, or a die formed from awafer. In some embodiments, the semiconductor substrate 202 is a siliconsubstrate. In some embodiments, the substrate 202 includes at least oneof silicon germanium, silicon carbide, gallium arsenic, galliumphosphide, indium phosphide, indium arsenide, indium antimonide or othersuitable semiconductor material. In some embodiments, the substrate 202includes other features such as a buried layer or an epitaxy layer. Insome embodiments, the semiconductor substrate 202 includes a doped epilayer. In some embodiments, the semiconductor substrate 202 includes asemiconductor layer overlying another semiconductor layer of a differenttype. In some embodiments, the semiconductor substrate 202 is a siliconlayer on a silicon germanium layer.

In some embodiments, at least some of the substrate 202 is formed ortreated by a first process 310. In some embodiments, the first process310 includes at least one of an epitaxy process, an implant process or abonding process. In some embodiments, the substrate 202 is grown by atleast one of solid-phase epitaxy (SPE) or vapor-phase epitaxy. In someembodiments, the first process 310 includes implanting a dopant. In someembodiments, the dopant is at least one of n-type or a p-type dopant. Insome embodiments, the n-type dopant includes at least one of arsenic orphosphorus. In some embodiments, the p-type dopant includes boron. Insome embodiments, the first process 310 includes a thermal process fordopant drive-in diffusion.

In some embodiments, the semiconductor device 200 is electricallyisolated from other devices by isolation structures 204 a-204 b. In someembodiments, at least one of the isolation structures 204 a-204 b isdisposed in the substrate 202. In some embodiments, at least one of theisolation structures 204 a-204 b is a shallow trench isolation (STI)structure. In some embodiments, the isolation structures 204 a-204 binclude a local oxidation of silicon (LOCOS) configuration. In someembodiments, at least one of the isolation structures 206 a-206 bincludes at least one of silicon oxide, silicon nitride, siliconoxynitride, fluoride-doped silicate glass (FSG) or a low-k dielectricmaterial.

At 104, a gate body 206 is formed, as illustrated in FIG. 3. In someembodiments, the gate body 206 includes at least one of an interfaciallayer 208, a gate dielectric layer 210, an interlayer dielectric (ILD)212, a work-function metal layer 214, sidewall spacers 216 or a cappinglayer 218.

In some embodiments, the interfacial layer 208 is formed on the sidewall spacers 216 as well as over the substrate 202. In some embodiments,the interfacial layer 208 includes a silicon oxide (SiO_(x)) layerhaving a thickness ranging from about 5 to about 50 angstroms. In someembodiments, the interfacial layer 208 includes at least one of HfSiO orSiON formed by at least one of atomic layer deposition (ALD), chemicalvapor deposition (CVD), physical vapor deposition (PVD), thermaloxidation and nitridation, plasma oxidation or nitridation.

In some embodiments, the gate dielectric layer 210 is formed over theinterfacial layer 208. In another embodiment, the interfacial layer 208is not present and the gate dielectric layer 210 is formed on thesidewall spacers 216 and over the substrate 202. In some embodiments,the gate dielectric layer 210 is a high-k dielectric layer. In someembodiments, the gate dielectric layer 210 is formed by at least one ofALD, CVD, metalorganic CVD (MOCVD), PVD, plasma enhanced CVD (PECVD),plasma enhance ALD (PEALD) or other suitable techniques. In someembodiments, the gate dielectric layer 210 is about 5 angstroms to about50 angstroms thick. In some embodiments, the gate dielectric layer 210includes a binary or ternary high-k film. In some embodiments, the gatedielectric layer 210 includes at least one of LaO, AlO, ZrO, TiO, Ta₂O₅,Y₂O₃, SrTiO₃ (STO), BaTiO₃ (BTO), BaZrO, HfOx, HfZrO, HfLaO, HfSiO,LaSiO, AlSiO, HfTaO, HfTiO, (Ba,Sr)TiO₃ (BST), Al₂O₃, Si₃N₄ oroxynitrides. In some embodiments, a post high-k deposition anneal isperformed as part of forming the gate dielectric layer 210.

In some embodiments, the ILD 212 includes an oxide formed by at leastone of a high aspect ratio process (HARP) or high density plasma (HDP)deposition process. In some embodiments, the deposition of the ILD 212fills in a gap between the semiconductor device 200 and an adjacentsemiconductor device.

In some embodiments, the work-function metal layer 214 is formed overthe gate dielectric layer 210. In some embodiments, the work-functionmetal layer 214 is an N-type or P-type work-function metal. In someembodiments, the work-function metal layer 214 is at least one oftitanium aluminide (TiAl), TiAl₃, nickel aluminide (NiAl) or ironaluminide (FeAl). In some embodiments, the work-function metal layer 214is between about 5 angstroms to about 100 angstroms thick. In someembodiments, the work-function metal layer 214 is formed using at leastone of an ALD, CVD or PVD process.

In some embodiments, the sidewall spacer 216 includes at least one ofsilicon nitride, silicon oxide, silicon carbide or silicon oxynitride.In some embodiments, the sidewall spacer 216 is about 3 nm to about 100nm wide.

In some embodiments, a capping layer 218 is formed over at least one ofthe gate dielectric layer 210 or the work-function metal layer 214. Insome embodiments, the capping layer 218 includes titanium nitride (TiN),tantalum nitride (TaN) or Si₃N₄. In some embodiments, the capping layer218 is about 5 angstroms to about 50 angstroms thick. In someembodiments, the capping layer 218 functions as a barrier to protect thegate dielectric layer 210. In some embodiments, the capping layer 218 isformed using at least one of an ALD, CVD or PVD process.

At 106, a conductive prelayer 232 is formed, as illustrated in FIG. 4.In some embodiments, the conductive prelayer 232 is formed over the gatebody 206. In some embodiments, the conductive prelayer 232 includes ametal. In some embodiments, the conductive prelayer 232 includes atleast one of aluminum (Al), copper (Cu), tungsten (W), titanium (Ti),tantalum (Ta), titanium nitride (TiN), titanium aluminide (TiAl),titanium aluminum nitride (TiAlN), tantalum nitride (TaN), nickelsilicon (NiSi) or cobalt silicon (CoSi). In some embodiments, theconductive prelayer 232 includes a conductive material with a workfunction. In some embodiments, the conductive prelayer 232 includes apoly. In some embodiments, the poly is a poly-silicon. In someembodiments, conductive prelayer 232 includes a doped poly-silicon withat least one of uniform or non-uniform doping. In some embodiments, theconductive prelayer 232 has a thickness of about 3 nm to about 200 nm.In some embodiments, the conductive prelayer 232 has a uniformthickness. In some embodiments, the conductive prelayer 232 is formedusing at least one of an ALD, CVD, PVD or plating process.

At 108, an opening 234 is formed, as illustrated in FIG. 5a and FIG. 5b. In some embodiments, the opening 234 is formed in the conductiveprelayer 232. In some embodiments, the opening 234 is defined by atleast one of a first sidewall 236 of the conductive prelayer 232, asecond sidewall 238 of the conductive prelayer 232 or a bottom portion239 of the conductive prelayer 232, as illustrated in FIG. 5b . In someembodiments, the opening 234 includes a top region width 240, a bottomregion width 242 or an opening height 244. In some embodiments, the topregion width 240 is about 1 nm to about 1000 nm. In some embodiments,the bottom region width 242 is about 2 angstroms to about 1000 nm. Insome embodiments, the opening height 244 is about 10 nm to about 1000nm. In some embodiments, the opening 234 is substantially V-shaped. Insome embodiments, the opening 234 has a tapered profile. In someembodiments, the top region width 240 is greater than the bottom regionwidth 242. In some embodiments, the top region width 240 is about 1.3 toabout 2.2 times greater than the bottom region width 242.

In some embodiments, the opening 234 is formed by a second process 320,as illustrated in FIG. 5a . In some embodiments, the second process 320includes an etching process. In some embodiments, the etching process ispreformed over a masking element and an exposed surface of theconductive prelayer 232. In some embodiments, the second process 320includes a dry etching process. In some embodiments, the etching processis a directional etching process. In some embodiments, the directionaletching process forms the tapered profile of the opening 234. In someembodiments, the directional etching process is performed such that thetop region width 240 is greater than the bottom region width 242. Insome embodiments, the etching process includes the use of at least oneof hydrogen fluoride (HF), sodium hydroxide (NaOH), chlorine (Cl₂),tetrafluoromethan (CF₄), sulfur hexafluoride (SF₆), or nitrogentrifluoride (NF₃). In some embodiments, the etching process includesexposing the conductive prelayer 232 to about 8 mTorr of SF₆ to about250 mTorr of SF₆.

At 110, a first inhibitor film 250 is formed, as illustrated in FIG. 6.In some embodiments, the first inhibitor film 250 is formed over atleast one of the first sidewall 236, the second sidewall 238 or thebottom portion 239. In some embodiments, a second inhibitor film 252 isformed over at least one of the first inhibitor film 250, the firstsidewall 236, the second sidewall 238 or the bottom portion 239. In someembodiments, the first inhibitor film 250 is formed on the firstsidewall 236 and the second inhibitor film 252 is formed on the secondsidewall 238. In some embodiments, the first inhibitor film 250 has atleast one of a first end 254 or a second end 256 and the secondinhibitor film 252 has at least one of a third end 258 or a fourth end260. In some embodiments, at least one of the first end 254 or the thirdend 258 is proximate a top portion of the gate body or distal from thesubstrate and at least one of the second end 256 or the fourth end 260is proximate a bottom portion of the gate body or proximate thesubstrate. In some embodiments, the first end 254 and the third end 258are spaced apart by a top distance and the second end 256 and the fourthend 260 are spaced apart by a bottom distance that is less than the topdistance.

In some embodiments, at least one of the first inhibitor film 250 or thesecond inhibitor film 252 is formed by a third process 330. In someembodiments, the third process 330 includes a passivation process. Insome embodiments, the passivation process includes exposing at least oneof the first sidewall 236, the second sidewall 238 or the bottom portion239 to a passivation gas. In some embodiments, passivation gas includesat least one of N₂, O₂ or CHF₃. In some embodiments, the passivation gasincludes at least one of about 15 sccm to about 500 sccm of N₂, about 5sccm to about 150 sccm of CHF₃ or about 5 sccm to about 150 sccm of O₂.In some embodiments, the passivation process is conducted with a powersource of about 100 W to 1500 W. In some embodiments, the passivationprocess is conducted with a bias power of about 0 W to about 450 W. Insome embodiments, the passivation process is conducted at a temperatureof about 30° C. to about 80° C. In some embodiments, at least some ofthe etching process and the passivation process are performedconcurrently. In some embodiments, a mixture gas includes thepassivation gas and the etching gas. In some embodiments, the mixturegas is used when the passivation process and the etching process arecarried out at the same time. In some embodiments, the mixture gasincludes about 8 sccm to about 250 sccm of SF₆, about 15 sccm to about500 sccm of N₂, about 5 sccm to about 150 sccm of Cl₂ and about 5 sccmto about 150 sccm of O₂.

In some embodiments, the third process 330 includes depositing at leastone of the first inhibitor film 250 or the second inhibitor film 252 onat least one of the first sidewall 236, the second sidewall 238 or thebottom portion 239. In some embodiments, at least one of the firstinhibitor film 250 or the second inhibitor film 252 is deposited usingat least one of an ALD, CVD or PVD process. In some embodiments, atleast one of the first inhibitor film 250 or the second inhibitor film252 includes at least one of a nitride, an oxide, a silicide or apolymer. In some embodiments, at least one of first inhibitor film 250or the second inhibitor film 252 includes a nonconductive material. Insome embodiments, at least one of the first inhibitor film 250 or thesecond inhibitor film 252 includes at least one of WN_(x), WO_(x),WSi_(x), or W(CH)_(x). In some embodiments, at least one of the firstinhibitor film 250 or the second inhibitor film 252 is configured toinhibit subsequent metal growth on at least one of the first sidewall236 or the second sidewall 238. In some embodiments, at least one of thefirst inhibitor film 250 or the second inhibitor film 252 is configuredto encourage any subsequent conductive material growth in the opening234 to occur in a bottom-to-top direction, as illustrated by arrow 253.In some embodiments, at least one of the first inhibitor film 250 or thesecond inhibitor film 252 is about 1 angstrom to about 200 angstromsthick.

At 112, a conductive layer 260 is formed, as illustrated in FIG. 7. Insome embodiments, the conductive layer 260 is formed over at least oneof the first inhibitor film 250, the second inhibitor film 252 or theconductive prelayer 232. In some embodiments, the conductive layer 260includes a metal. In some embodiments, the conductive layer 260 includesat least one of aluminum (Al), copper (Cu), tungsten (W), titanium (Ti),tantalum (Ta), titanium nitride (TiN), titanium aluminide (TiAl),titanium aluminum nitride (TiAlN), tantalum nitride (TaN), nickelsilicon (NiSi) or cobalt silicon (CoSi). In some embodiments, theconductive layer 260 includes a conductive material with a workfunction. In some embodiments, the conductive layer 260 includes a poly.In some embodiments, the poly is a poly-silicon. In some embodiments,conductive layer 260 includes a doped poly-silicon with at least one ofuniform or non-uniform doping. In some embodiments, the conductiveprelayer 232 and the conductive layer 260 include the same conductivematerial. In some embodiments, the conductive layer 260 is formed usingat least one of an ALD, CVD, PVD or plating process. In someembodiments, the conductive layer 260 is formed by depositing aconductive material in the opening 234 proximate the bottom portion 239and filling the opening therefrom in the direction represented by thearrow 253. In some embodiments, the tapered shape of the opening 234inhibits the formations of seams or voids in the conductive prelayer 232and the conductive layer 260. In some embodiments, the tapered shape ofthe opening 234 facilitates evenly and consistently depositing at leastone of the conductive prelayer 232 or the conductive layer 260. In someembodiments, the conductive layer 260 has a top portion width 241 and abottom portion width 243, where the top portion width 241 is greaterthan the bottom portion width 243. In some embodiments, the top portionwidth 241 of the conductive layer 260 reflects the top region width 240of the opening 234 and the bottom portion width 243 of the conductivelayer 260 reflects the bottom region width 242 of the opening 234.

In some embodiments, the semiconductor device 200 includes other layersor features not specifically illustrated including at least one of asource, a drain, a contact, an interconnect or other suitable features.In some embodiments, other back end of line (BEOL) processes arepreformed on the semiconductor device 200.

According to some aspects of the instant disclosure, a semiconductordevice is provided. The semiconductor device comprising a gate body, aconductive prelayer over the gate body, a conductive layer over theconductive prelayer and a first inhibitor film between at least part ofthe conductive prelayer and the conductive layer. In some embodiments,the first inhibitor film has a first end proximate the gate body topportion and a second end proximate the gate body bottom portion. In someembodiments, the first end is a first distance from the first gate bodysidewall and the second end is a second distance from the first gatebody sidewall. In some embodiments, the second distance is greater thanthe first distance. The gate body comprising a first gate body sidewall,a second gate body sidewall, a gate body top portion and a gate bodybottom portion.

According to some aspects of the instant disclosure, a method of forminga semiconductor device is provided. The method comprising forming aconductive prelayer over a gate body, forming an opening in theconductive prelayer, the opening defined by a first sidewall of theconductive prelayer, a second sidewall of the conductive prelayer and abottom portion of the conductive prelayer, forming a first inhibitorfilm on at least one of the first sidewall, the second sidewall or thebottom portion, and forming a conductive layer over the first inhibitorfilm. In some embodiments, the opening has a top region width and abottom region width, wherein the top region width is greater than thebottom region width.

According to some aspects of the instant disclosure, a method of forminga semiconductor device is provided. The method comprising forming a gatebody over a substrate, a conductive prelayer over the gate body, a firstinhibitor film over the conductive prelayer and a conductive layer overthe first inhibitor film. In some embodiments, the conductive layer hasa top portion width and a bottom portion width, the top portion widthgreater than the bottom portion width.

The foregoing outlines features of several embodiments so that thoseskilled in the art may better understand the aspects of the presentdisclosure. Those skilled in the art should appreciate that they mayreadily use the present disclosure as a basis for designing or modifyingother processes and structures for carrying out the same purposes and/orachieving the same advantages of the embodiments introduced herein.Those skilled in the art should also realize that such equivalentconstructions do not depart from the spirit and scope of the presentdisclosure, and that they may make various changes, substitutions, andalterations herein without departing from the spirit and scope of thepresent disclosure.

Various operations of embodiments are provided herein. The order inwhich some or all of the operations are described should not beconstrued as to imply that these operations are necessarily orderdependent. Alternative ordering will be appreciated given the benefit ofthis description. Further, it will be understood that not all operationsare necessarily present in each embodiment provided herein. Also, itwill be understood that not all operations are necessary in someembodiments.

Further, unless specified otherwise, “first,” “second,” or the like arenot intended to imply a temporal aspect, a spatial aspect, an ordering,etc. Rather, such terms are merely used as identifiers, names, etc. forfeatures, elements, items, etc. For example, a first channel and asecond channel generally correspond to channel A and channel B or twodifferent or two identical channels or the same channel.

It will be appreciated that layers, features, elements, etc. depictedherein are illustrated with particular dimensions relative to oneanother, such as structural dimensions or orientations, for purposes ofsimplicity and ease of understanding and that actual dimensions of thesame differ substantially from that illustrated herein, in someembodiments. Additionally, a variety of techniques exist for forming thelayers, regions, features, elements, etc. mentioned herein, such asimplanting techniques, doping techniques, spin-on techniques, sputteringtechniques, growth techniques, such as thermal growth or depositiontechniques such as chemical vapor deposition (CVD), physical vapordeposition (PVD), plasma enhanced chemical vapor deposition (PECVD), oratomic layer deposition (ALD), for example.

Moreover, “exemplary” is used herein to mean serving as an example,instance, illustration, etc., and not necessarily as advantageous. Asused in this application, “or” is intended to mean an inclusive “or”rather than an exclusive “or”. In addition, “a” and “an” as used in thisapplication are generally be construed to mean “one or more” unlessspecified otherwise or clear from context to be directed to a singularform. Also, at least one of A and B or the like generally means A or Bor both A and B. Furthermore, to the extent that “includes”, “having”,“has”, “with”, or variants thereof are used in either the detaileddescription or the claims, such terms are intended to be inclusive in amanner similar to the term “comprising”.

Also, although the disclosure has been shown and described with respectto one or more implementations, equivalent alterations and modificationswill occur to others skilled in the art based upon a reading andunderstanding of this specification and the annexed drawings. Thedisclosure includes all such modifications and alterations and islimited only by the scope of the following claims. In particular regardto the various functions performed by the above described components(e.g., elements, resources, etc.), the terms used to describe suchcomponents are intended to correspond, unless otherwise indicated, toany component which performs the specified function of the describedcomponent (e.g., that is functionally equivalent), even though notstructurally equivalent to the disclosed structure. In addition, while aparticular feature of the disclosure may have been disclosed withrespect to only one of several implementations, such feature may becombined with one or more other features of the other implementations asmay be desired and advantageous for any given or particular application.

What is claimed is:
 1. A semiconductor device, comprising: a firstsidewall spacer; a second sidewall spacer; a gate dielectric between thefirst sidewall spacer and the second sidewall spacer; a conductivepre-layer over the gate dielectric and between the first sidewall spacerand the second sidewall spacer; a first inhibitor film in direct contactwith the conductive pre-layer, over the conductive pre-layer, andbetween the first sidewall spacer and the second sidewall spacer; asecond inhibitor film in direct contact with the conductive pre-layer,over the conductive pre-layer, and between the first sidewall spacer andthe second sidewall spacer; and a conductive layer over the firstinhibitor film and the second inhibitor film and between the firstsidewall spacer and the second sidewall spacer, wherein, in an areabetween the first sidewall spacer and the second sidewall spacer: theconductive layer has a first width at a first height above a substrateunderlying the conductive layer, at the first height, the conductivelayer is laterally coincident with the first inhibitor film, the firstwidth is measured in a first direction extending from the first sidewallspacer to the second sidewall spacer, the first height is measured in asecond direction perpendicular to the first direction and perpendicularto a top surface of the substrate, the conductive layer has a secondwidth, measured in the first direction, at a second height, measured inthe second direction, above the substrate, at the second height, theconductive layer is laterally coincident with the first inhibitor film,the first width is less than the second width, and the first height isless than the second height.
 2. The semiconductor device of claim 1,wherein, in the area between the first sidewall spacer and the secondsidewall spacer: the conductive pre-layer has a first thickness at athird height above the substrate, at the third height, the conductivepre-layer is laterally coincident with the first inhibitor film, thefirst thickness is measured in the first direction, the third height ismeasured in the second direction, the conductive pre-layer has a secondthickness, measured in the first direction, at a fourth height, measuredin the second direction, above the substrate, at the fourth height, theconductive pre-layer is laterally coincident with the first inhibitorfilm, the first thickness is greater than the second thickness, and thethird height is less than the fourth height.
 3. The semiconductor deviceof claim 1, wherein the second inhibitor film is spaced apart from thefirst inhibitor film by the conductive layer.
 4. The semiconductordevice of claim 1, wherein: the first inhibitor film is in directcontact with a first portion of an upper surface of the conductivepre-layer, the conductive layer is in direct contact with a secondportion of the upper surface of the conductive pre-layer, the secondinhibitor film is in direct contact with a third portion of the uppersurface of the conductive pre-layer, and the second portion of the uppersurface of the conductive pre-layer is between the first portion of theupper surface of the conductive pre-layer and the third portion of theupper surface of the conductive pre-layer.
 5. The semiconductor deviceof claim 1, wherein the conductive pre-layer comprises at least one of ametal or polysilicon.
 6. The semiconductor device of claim 1, whereinthe first inhibitor film comprises tungsten.
 7. The semiconductor deviceof claim 1, wherein the first inhibitor film comprises at least one ofWN_(x), WO_(x), WSi_(x), or W(CH)_(x), where x is a positive value. 8.The semiconductor device of claim 1, wherein the conductive pre-layerand the conductive layer have a same composition.
 9. The semiconductordevice of claim 1, comprising: a work-function metal layer between thegate dielectric and the conductive pre-layer.
 10. The semiconductordevice of claim 1, comprising: an interfacial layer under the gatedielectric and between the first sidewall spacer and the second sidewallspacer.
 11. The semiconductor device of claim 1, comprising: a cappinglayer between the gate dielectric and the conductive pre-layer.
 12. Asemiconductor device, comprising: a first sidewall spacer; a secondsidewall spacer; a gate dielectric between the first sidewall spacer andthe second sidewall spacer; a first inhibitor film over the gatedielectric and between the first sidewall spacer and the second sidewallspacer, wherein a distance between the gate dielectric and the firstinhibitor film, measured in a first direction, varies as a function ofheight, measured in a second direction perpendicular to the firstdirection; a second inhibitor film over the gate dielectric and betweenthe first sidewall spacer and the second sidewall spacer, wherein thesecond inhibitor film is spaced apart from the first inhibitor film; aconductive pre-layer between the gate dielectric and the first inhibitorfilm; and a conductive layer over the first inhibitor film, wherein theconductive layer is in direct contact with the conductive pre-layer. 13.The semiconductor device of claim 12, wherein the conductive layer isbetween a bottom edge of the first inhibitor film and a bottom edge ofthe second inhibitor film.
 14. The semiconductor device of claim 12,wherein, in an area between the first sidewall spacer and the secondsidewall spacer: the first inhibitor film is separated from the secondinhibitor film by a first distance at a first height above a substrateunderlying the first inhibitor film, the first distance is measured inthe first direction, the first direction extends from the first sidewallspacer to the second sidewall spacer, the first height is measured inthe second direction, the second direction is perpendicular to a topsurface of the substrate, the first inhibitor film is separated from thesecond inhibitor film by a second distance, measured in the firstdirection, at a second height, measured in the second direction, abovethe substrate, the first distance is less than the second distance, andthe first height is less than the second height.
 15. The semiconductordevice of claim 12, wherein the conductive pre-layer and the conductivelayer have a same composition.
 16. The semiconductor device of claim 12,comprising: a work-function metal layer between the gate dielectric andthe conductive pre-layer.
 17. A semiconductor device, comprising: afirst sidewall spacer; a second sidewall spacer; a gate dielectricbetween the first sidewall spacer and the second sidewall spacer; and afirst inhibitor film over the gate dielectric and between the firstsidewall spacer and the second sidewall spacer, wherein: the firstinhibitor film is separated from the first sidewall spacer by a firstdistance at a first height above a substrate underlying the firstinhibitor film, the first distance is measured in a first directionextending from the first sidewall spacer to the second sidewall spacer,the first distance is measured from a surface of the first inhibitorfilm closest to the first sidewall spacer to a surface of the firstsidewall spacer closest to the first inhibitor film, the first height ismeasured in a second direction perpendicular to the first direction andperpendicular to a top surface of the substrate, the first inhibitorfilm is separated from the first sidewall spacer by a second distance,measured in the first direction, at a second height, measured in thesecond direction, above the substrate, the second distance is measuredfrom the surface of the first inhibitor film closest to the firstsidewall spacer to the surface of the first sidewall spacer closest tothe first inhibitor film, the first distance is greater than the seconddistance, and the first height is less than the second height.
 18. Thesemiconductor device of claim 17, comprising: a conductive pre-layerbetween the gate dielectric and the first inhibitor film.
 19. Thesemiconductor device of claim 17, comprising: a conductive layer overthe first inhibitor film and between the first sidewall spacer and thesecond sidewall spacer.
 20. The semiconductor device of claim 17,wherein the first inhibitor film comprises at least one of WN_(x),WO_(x), WSi_(x), or W(CH)_(x), where x is a positive value.